Easy numbers

June 5, 2018

Some numbers are easier to work with than others, especially for computer arithmetic—and even more so with weak processors. So let’s have a look at easy numbers that we can sometimes exploit to get faster code.

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Yes? No? Maybe? (Part II)

March 27, 2018

Last week, we had a look at how to implement a trool, or a tri-valued boolean what accepts true, false, and undefined. We remarked that the storage of an enum likely defaults to int, and that my poc wouldn’t play well with std::vector as that container has no specialization to deal with this new type.

A specialization would be interesting because we can do much better than using an integer to store three different values. We can do much, much better.

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Fractional Bits (Part II)

March 4, 2014

In a previous post, we started discussing the subject of encoding values using fractional bits. This is quite counter-intuitive as we usually think that encoding asks for whole bits, furthermore that we think of bits as being essentially atomic—unsplittable.

pincer-grip

However, bits can be fractioned, helping us devising efficient encodings, something not unlike a primitive form of arithmetic coding, for a variety of data. Let’s consider a simple case that illustrates the principle: encoding the date.

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